Sound producer



Jan. 3,1939. CROUSHORE 2,142,222

SOUND PRODUCER Filed.Sept. 12, 1956 INVENTOR GERALD C. CROUSHORE.

ATTORNEY Patented Jan. 3, 1939 UNITED STATES SOUND PRODUCER Gerald G. Croushore, East McKeesport, Pa., as-

signor to Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application September 12, 1936, Serial No. 100,478

7 Claims.

This case relates to sound producers and more particularly to the type operated by fluid pressure.

One object of the invention is to provide an improved signaling or sound producing device having a fluid pressure operated vibratory diaphragm and means cooperative therewith for producing a distinctive, musical note.

Another object of the invention is to provide an improved sound producing device having a diaphragm operative by fluid under pressure to control the release of fluid under pressure from a chamber and fluid pressure resonant means responsive to pulsations in the pressure of fluid released from the chamber to produce an amplified sound of considerable carrying capacity.

A further object of the invention is to provide a fluid pressure operated sound producing device comprising a vibratory diaphragm for controlling the release of fluid from a chamber at the face thereof, and a resonating chamber for amplifying the vibrations produced by the diaphragm in the surrounding atmosphere, the resonating chamber being also operative by the fluid released by the diaphragm to produce vibrations in the surrounding atmosphere.

In the accompanying drawing, the single figure is a vertical sectional view of a sound producing device constructed in accordance with the invention.

Referring to the drawing, the sound producing device comprising a body I having a bracket portion 2 which is secured to a support 3 by means of a clamping member 4 and screws 5 which extend through openings in the member 4 and have screw-threaded engagement in the bracket portion 2. A substantially spheroidal resonant bell 6 is provided which is hollow and relatively thin walled and is provided with an annular neck portion I surrounding an opening 8 in the bell and terminating in a sharp annular edge 9.

The bell 6 is carried by a coaxially disposed stem l0 having one end II in screw-threaded connection with the body. The stem It extends upwardly through the opening 8 and at the upper end I2 is secured to the bell 6 by means of a screw l3. A gasket I4 is preferably interposed between the end l2 of the stem and the bell 6, the gasket being of such thickness as to permit the annular edge 9 of the neck 1 of the bell to be concentrically aligned with and to project slightly into a circular cavity l5 formed in the body I.

A flexible diaphragm ll of a diameter slightly less than that of the annular edge 9 is mounted on the lower end ll of the stem l9 within the cavity I5, the diaphragm being clamped between a collar l8 formed on the stem and a nut l9. An annular seat rib 20 formed on the body I is adapted for engagement with the under face of the diaphragm ll near the periphery thereof,

and the desired positioning of the diaphragm relative to the seat rib may be efiected by adjustment of the screw-threaded end ll of the stem in the body. For holding the stem II) in the adjusted position a lock nut 2| is provided on the portion of the end II projecting beyond the body I.

Formed at the lower side of the diaphragm l'l within the seat rib 20 is a chamber 23 communieating by way of a passage 24 having a restricted portion 25, with a pipe 26, which is adapted to be supplied with fluid under pressure in any desired manner for operating the sound producing device.

In operation fluid under pressure supplied by way of the pipe 26, restricted passage 25 and passage 24 to the chamber 23 rapidly builds up sufficient fluid pressure therein to force the peripheral portion of the diaphragm H from the seat rib 29. The diaphragm I1 is thus moved far enough to permit the fluid underpressure to' be quickly vented from the chamber 23 past the diaphragm to the cavity l5, where it impinges against the annular edge 9 of the spheroidal bell 6, causing vibration of the air within and surrounding the edge so as to produce sound; which is intensified due to resonance of the air within the bell.

Because of its inertia the diaphragm ll will continue to move away from the seat rib 20 far enough to provide a flow area around the diaphragm suchthat fluid is vented from the chamber 23 at a rate faster than that at which fluid under pressure is supplied to the chamber 23 by way of the restricted passage 25. As a result there will be a rapid reduction in the pressure of the fluid in the chamber 23 and a corresponding reduction in the force exerted on the diaphragm ll, so that the diaphragm will spring back into engagement with the seat rib 29 to cut off the release of fluid under pressure from the chamber. Continued supply of fluid under pressure through the restricted passage 25 will then quickly. build up the fluid pressure in the chamber 23 untilthe diaphragm ll is again moved away from the seat rib 20.

The diaphragm I! is thus caused to vibrate rapidly, so as to effect pulsations in the flow of fluid under pressure released from the chamber 23 which impinges against the edge 9 of the resonant bell 6, and the sound thus produced by im ducing sound supplementing and harmonizing with the sound produced by impingement of fluid under pressure on the edge 9 of the bell.

It will be understood that the bell 6 is so de- H of the air within and adjacent the bell 6, pro-' signed and proportioned in size, area and thickness as to resonate in response to the vibrations produced by the diaphragm l1 repeatedly striking the seat rib 20, and that in addition, the period of sound producing vibrations of the air within the bell caused by impingement of fluid under pressure released from the chamber 23 against the edge 9 will be such as to effect blending of both sounds for producing a warning note of the desired tone and pitch.

It will thus be seen that the invention provides an improved sound producing device of sturdy construction and having relatively few parts, which device includes a fluid pressure operated vibratory diaphragm and fluid pressure resonant means arranged to amplify vibrations produced by the diaphragm and to be subjected to fluid under pressure vented past the diaphragm for producing a signal of pleasing tonal quality and great penetrating power.

' Having now described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a sound producing device comprising a "body having a chamber, a vibratory diaphragm operative by fluid under pressure supplied to said chamber to effect periodic release of fluid under pressure therefrom, and hollow spheroidal resonant means carried by said body, said means having a lip surrounding a constantly open atmospheric passage leading to the chamber withins'aid resonant means and disposed adjacent said diaphragm, whereby the edge of said lip causes pulsation of the air within said hollow resonant means in response to the flow of fluid under pressure from the chamber in said body past said diaphragm.

2. A sound producing device comprising, in

' combination, a body having a chamber, a vibratory diaphragm operative by fluid under pressure supplied to said chamber to effect periodic release'of fluid under pressure therefrom,-a hollow spheroidal bell carried by said body and adapted to resonate in response to a given irequency of vibration of the air therein,-said bell having a lip surrounding an always open atmos- 'phe'ric passage leading to the chamber within said bell and disposed adjacent said diaphragm,

"whereby the edge of said lip causes pulsation of theair within said bell in response to the flow of fluid under pressure from the chamber in said body past said diaphragm, and means for adjusting said diaphragm to vary the period of vibration thereof.

3. In a sound producing device, in combination, a casing having a chamber and an annular seat 'rib defining a wall of said chamber, a stem -'adjustab1y mounted on said casing, a vibratory diaphragm centrally secured to the stem adjacent said chamber and operative into and out of engagement with said rib by fluid underpressure supplied to said chamber-to "control the re- -lease-of fluid under pressure from said chamber pastsaid rib, and fluid pressure resonant means carried by said stem and adapted to effect reson'anceof the-sound producedby said diaphragm and responsive to fluid under pressure released from the chamber for independently producing "sound.

' cavityand a=central chamber in the'face-thereof,

a-seat rib formed-on said -member-inwardly of.

therein said body being provided with a neck portion of larger diameter than said diaphragm and of smaller diameter than said cavity and having an openingcommunicating with the atmosphere, said neck portion extending into said cavity and being disposed concentrically thereof. 5. In a sound-producing device, in combination, -a member having a substantially circular cavity and a central chamber in the face thereof,

a seat rib formed on said member inwardly of the wall of said cavity and defining a Wall of said chambenan element secured to said member, a

vibratorydiaphragm carried by said element and engageable with said seat rib to control the flow of fluid under pressure from the chamber within the seat rib to the area outwardly thereof, said :diaphragm being of larger diameter than said seat rib and of smaller diameter than said cavity, and a body carried by said member and having a resonating chamber therein, said body being provided with a neck portion of larger diameter than said diaphragm and of smaller diameter than said cavity and having an opening communicating with the atmosphere, the

tion, a casing having a chamber and an annular seat rib defining a wall of said chamber, a

stem adjustably mounted on said casing, a vibratory diaphragm centrally secured to the stem --adjacent said chamber and operative into and out of engagement with said rib by fluid under pressure supplied to said chamber to control the release of fluid under pressure from said chamber past said rib, a hollow resonant element secured to the end of said stem and having a resonating chamber and a single opening, and a cylindrical neck carried on said element surrounding said opening, said neck terminating in an annular edge positioned adjacent the peripheral portion of the face of said diaphragm opposite said rib.

'7. Ina sound producing device, in combination, a casing having a -chamber and an annular seat rib defining a wall of said chamber, a stem adjustably mounted on said casing, a vibratory "diaphragm centrally secured to the stem adjacent said chamber and having its peripheral portion 'movable into and out of seating engage ment with said rib by fluid under pressure supplied to said-chamber to permit periodic release of fluid from said chamber past said riband said peripheral portion, and a fluid pressure resonant elementremovably mounted on said stem and having a resonating chamber and an annular lip surrounding an opening leading to the resonating chamber, said lip being of substantially-the same diameter as said diaphragm and being disposed adjacent thereto for receiving fluid under pressure discharged from the first named chamber.

the wall-of said cavity and defining a wall of said -GERALD C. CROUSHORE. 

